ABSTRACT

A natural environmental information and impact assessment system has been developed to provide local decision-makers with ready access to environmental data and to allow them to explore the natural environmental consequences of development activities. This system, operational on the Rice University computer facility, currently serves Chambers County, Texas. The system consists of three major elements: 1) a natural environmental data base, 2) a data storage-retrieval and display capability; and 3) an impact assessment routine. Interaction between the user and the system is conducted entirely in an on-line conversational mode.

The data base is coded in the form of 3,200 uniform rectangular grid cells referenced to the latitude-longitude coordinate system. Each cell contains data describing 83 natural environmental variables. The system's storage-retrieval and display capability allows the user to update the data base, to retrieve information, and to perform fundamental data processing functions. Maps can be produced showing the spatial distribution of various natural features.

The impact assessment routine was developed in the form of 24 sub-models each describing the relationship between eight major land-use categories and particular aspects of the natural system. In terms of information flow, a proposed development, described in terms of its constituent land-uses, is first evaluated with respect to characteristics of the proposed site to determine the existence of natural or man-made encumbrances. The land-uses are then described in terms of the input they make into the natural system. Depending upon the type of input in question a particular sequence of evaluations is performed, in conjunction with the data base, to estimate the magnitude of the impacts created. The results of this assessment are then displayed to the user in the form of a brief narrative report.